So over half of the home buyers in LA are first time home buyers, or maybe not:
"The data only look at the share of homes being financed with conventional loans or FHA-backed mortgages. Because most of the all-cash purchases probably aren’t first-time buyers, the total share of homes being purchased by first-time buyers is lower...(therefore), the reported share of first-time buyers also could be higher in more expensive states due to the conforming loan limits. Fannie and Freddie, for example, can’t buy loans that exceed $417,000, though the limit was increased for certain high-cost areas in 2008. It currently runs as high as $625,500 in the more expensive markets. This means a significant share of more expensive home sales—which are less likely to include first time buyers—aren’t captured in the data.
The fact that a larger portion of loans would be excluded from the analysis in more expensive states could make state-by-state comparisons less revealing. But the data still provide an interesting view of how the first-time borrower component has changed over time within a particular state. They show that first-time buyers continue to make up a higher-than-average share of borrowers, even if they are off of their 2009 highs."
The linked heatmap shows the share of mortgages guaranteed by Fannie Mae, Freddie Mac and the Federal Housing Administration that went to first-time buyers.
First-Time Home Buyers - WSJ.com